Do you checkpoint uninterruptible syscalls as well? If only interruptiblesyscalls are checkpointed, I'd say that either this syscall uses ERESTARTSYS orERESTART_RESTARTBLOCK, and then signal handling code already does the trick, orthis syscall does not restart itself when interrupted, and well, this is life,userspace just sees -EINTR, which is allowed by the syscall spec.Actually this is how we checkpoint/migrate tasks in interruptible syscalls inKerrighed and this works.